Method of servicing an airfoil assembly for use in a gas turbine engine

Abstract

A method of servicing an airfoil for use in a gas turbine engine. The airfoil assembly is defined by a base material and includes an airfoil and a platform from which the airfoil extends. A predetermined amount of the base material is removed from the airfoil assembly proximate to a fillet area of the airfoil assembly via water jet material removal. The fillet area comprises a junction between the airfoil and the platform and is located at an intersection between the airfoil and the platform. A remainder of the base material comprising base material of the airfoil assembly other than proximate to the fillet area is left intact.

What is claimed is: 
     
       1. A method of servicing an airfoil assembly for use in a gas turbine engine, the airfoil assembly defined by a base material and comprising an airfoil having a radially inner end which is attached to a platform from which the airfoil extends, the method comprising:
 removing predetermined amounts of the base material from the airfoil assembly proximate to a fillet area and the radially inner end of the airfoil assembly at leading and trailing edges of the airfoil and at a location between the leading and trailing edges via water jet material removal, the fillet area comprising a junction between the airfoil and the platform and located at an intersection between the airfoil and the platform; 
 wherein a remainder of the base material comprising base material of the airfoil assembly other than proximate to the fillet area is left intact; 
 wherein a radius of curvature at the fillet area of the resulting structure after said removing is at least as large as a radius of curvature at the fillet area before said removing; and 
 wherein the predetermined amounts of the base material that are removed from the airfoil assembly at the leading and trailing edges of the airfoil and at the location between the leading and trailing edges of the airfoil are dependent upon a thickness of the fillet area at these locations so as to remove the predetermined amounts of the base material including any defects in the base material at these locations such that, after the base material is removed, a structural rigidity of the airfoil is maintained at the fillet area. 
 
     
     
       2. The method of  claim 1 , further comprising stripping at least one coating from the airfoil assembly prior to said removing. 
     
     
       3. The method of  claim 1 , wherein said removing comprises:
 removing a first portion of the base material from the airfoil; and 
 removing a second portion of the base material from the platform. 
 
     
     
       4. The method of  claim 3 , wherein said removing a first portion of the base material from the airfoil comprises removing base material starting from a location about 1 inch radially outwardly from the intersection between the airfoil and the platform. 
     
     
       5. The method of  claim 4 , wherein said removing a second portion of the base material from the platform comprises removing base material to a location about 1 inch removed from the intersection between the airfoil and the platform along a length of the platform. 
     
     
       6. The method of  claim 1 , wherein said removing comprises removing an amount of material corresponding to a depth of the base material at the fillet area measured from an outer surface of the base material of from about 0.030 inch to about 0.080 inch. 
     
     
       7. The method of  claim 1 , wherein said removing comprises removing an amount of material corresponding to a depth of the base material at the fillet area measured from an outer surface of the base material of about 0.060 inch. 
     
     
       8. The method of  claim 1 , wherein said removing comprises varying the amount of the base material that is removed from the leading edge to the trailing edge of the airfoil. 
     
     
       9. The method of  claim 8 , wherein the amount of the base material that is removed proximate to the leading and trailing edges of the airfoil is less than the amount of the base material that is removed at the location between the leading and trailing edges of the airfoil. 
     
     
       10. The method of  claim 8 , wherein the amount of the base material that is removed proximate to the leading edge of the airfoil is more than the amount of the base material that is removed at the trailing edge of the airfoil. 
     
     
       11. A method of servicing an airfoil assembly for use in a gas turbine engine, the airfoil assembly defined by a base material and comprising an airfoil having a radially inner end which is attached to a platform from which the airfoil extends, the method comprising:
 removing predetermined amounts of the base material from the airfoil assembly proximate to a fillet area and the radially inner end of the airfoil assembly at leading and trailing edges of the airfoil and at a location generally midway between the leading and trailing edges via water jet material removal, the fillet area comprising a junction between the airfoil and the platform and located at an intersection between the airfoil and the platform; 
 wherein a remainder of the base material comprising base material of the airfoil assembly other than proximate to the fillet area is left intact; 
 wherein said removing comprises varying the amount of the base material that is removed from the leading edge to the trailing edge of the airfoil; and 
 wherein the predetermined amounts of the base material that are removed from the airfoil assembly at the leading and trailing edges of the airfoil and at the location generally midway between the leading and trailing edges of the airfoil are dependent upon a thickness of the fillet area at these locations so as to remove the predetermined amounts of the base material including any defects in the base material at these locations such that, after the base material is removed, a structural rigidity of the airfoil is maintained at the fillet area. 
 
     
     
       12. The method of  claim 11 , wherein said removing comprises:
 removing a first portion of the base material from the airfoil; and 
 removing a second portion of the base material from the platform. 
 
     
     
       13. The method of  claim 12 , wherein:
 said removing a first portion of the base material from the airfoil comprises removing base material starting from a location about 1 inch radially outwardly from the intersection between the airfoil and the platform; and 
 said removing a second portion of the base material from the platform comprises removing base material to a location about 1 inch removed from the intersection between the airfoil and the platform along a length of the platform. 
 
     
     
       14. The method of  claim 11 , wherein said removing comprises removing an amount of material corresponding to a depth of the base material at the fillet area measured from an outer surface of the base material of from about 0.030 inch to about 0.080 inch. 
     
     
       15. The method of  claim 11 , wherein the amount of the base material that is removed proximate to the leading and trailing edges of the airfoil is less than the amount of the base material that is removed at the location generally midway between the leading and trailing edges of the airfoil. 
     
     
       16. The method of  claim 15 , wherein the amount of the base material that is removed proximate to the leading edge of the airfoil is more than the amount of the base material that is removed at the trailing edge of the airfoil. 
     
     
       17. The method of  claim 11 , wherein a radius of curvature at the fillet area of the resulting structure after said removing is at least about 0.26 inch. 
     
     
       18. The method of  claim 17 , wherein the radius of curvature at the fillet area of the resulting structure after said removing is substantially the same as a radius of curvature at the fillet area before said removing. 
     
     
       19. The method of  claim 16 , wherein:
 the amount of the base material that is removed proximate to the leading edge of the airfoil is about half of the amount of base material that is removed at the location generally midway between the leading and trailing edges of the airfoil; and 
 the amount of the base material that is removed proximate to the trailing edge of the airfoil is about half of the amount of base material that is removed proximate to the leading edge of the airfoil.